25111-05-1Relevant articles and documents
Microwave barrel reactor use in trimethylolpropane oleate synthesis by Candida antarctica lipase in a biphasic non-solvent process
Happe, Manuel,Grand, Pascal,Farquet, Sebastien,Aeby, Sandrine,Heritier, Jean-Claude,Corthay, Francois,Mabillard, Eric,Marti, Roger,Vanoli, Ennio,Grogg, Alain-Francois,Nussbaum, Samuel,Roduit, Alain,Tieche, Francois,Salem, Sam,Constantin, Carole,Schmitt, Esther,Zahno, Silvan,Ellert, Christoph,Habib, Ahmed,Wyss, Julien,Fischer, Fabian
, p. 2337 - 2345 (2012)
A novel microwave barrel reactor (MBR) was constructed and used in lipase catalyzed biolubricant synthesis. The MBR is thought as a versatile process tool for biotransformation and green chemistry that overcomes current size limitations in microwave reactors. A lipase mediated biotransformation in the MBR was compared to a state of the art jacketed reactor with external heat exchanger. Oleic acid and trimethylolpropane converted quantitatively (96%) into biolubricants using microwave induction. The heat dissipation in the MBR was analyzed by thermal imaging and inside thermometry. Conversion rates, rate constants and pseudo reaction orders were in line with conventional processing and no microwave effect was detected. The MBR is a versatile new reactor for non solvent, minimal and common solvent processing in the microwave field. While the subject of investigations was biolubricant synthesis in the MBR, the technology described is of wider potential interest in the field of biomass processing and sustainable chemical manufacture.
Behavior of cation-exchange resins employed as heterogeneous catalysts for esterification of oleic acid with trimethylolpropane
Kuzminska, Maryna,Backov, Rénal,Gaigneaux, Eric M.
, p. 11 - 16 (2015)
Four cation-exchange resins (Dowex 50wx2, Amberlyst 36, Purolite CT482 and Purolite CT275DR) were investigated as catalysts in the esterification of oleic acid (OA) with trimethylolpropane (TMP). All four resins accelerated the reaction kinetics. The results showed that in a solvent-free system, the gel-type resin Dowex 50wx2 must be pre-swollen prior the reaction to achieve high catalytic performance. Contrary, the macro-reticular Amberlyst 36, Purolite CT482 and Purolite CT275DR do not need any pre-treatment to be active. The latter is due to the high crosslinking degree of these resins. Recyclability tests showed that the resins slightly lose their activity after the first use but retain stable activity during the further uses. The activity decay of the recycled resins is referred to the partial blocking of the active sites by the co-produced water. Additional studies confirmed the high stability of the chosen resins toward leaching in polar medium. Overall, both high stability and possibility of reusing through still high catalytic activity make the resins attractive candidates as heterogeneous catalysts for such complex industrial process.
Immobilizing heteropolyacids on zirconia-modified silica as catalysts for oleochemistry transesterification and esterification reactions
Kuzminska, Maryna,Kovalchuk, Tetyana V.,Backov, Rénal,Gaigneaux, Eric M.
, p. 1 - 8 (2015/09/28)
A new method of chemical immobilization of Keggin heteropolyacids (HPAs) was suggested. H3PW12O40, H4SiW12O40, and H3PMo12O40 were immobilized on the silica which was previously grafted with zirconium butoxide. The immobilization method promoted strong interaction HPA-support and yielded 25 wt.% of well-dispersed HPAs, so increasing the density of acid sites. The catalysts were active in the reaction of transesterification of methyl stearate with n-butanol and esterification of oleic acid with trimethylolpropane. We demonstrate that, contrary to the immobilized H3PMo12O40, the H3PW12O40 and H4SiW12O40-based catalysts are stable toward leaching in a non-polar oleic acid medium. A discussion on circumventing the leaching in non-polar versus polar media is proposed in terms of interaction strength HPA-support. The stronger interaction (i.e., better resistance for leaching) between the support and H3PW12O40 (or H4SiW12O40) is referred to the lower difference of electronegativity between Zr and W and the lower polarizability of the bonds Zr-O-W compared to Zr-O-Mo.
